Image Compressor
Drop in an image and adjust the quality slider to shrink its file size, with a live before/after comparison. Re-encoding happens locally using the browser's canvas API — nothing is uploaded anywhere. Works best on photos; choose JPEG for photos without transparency or WebP for the best size-to-quality ratio.
Frequently asked questions
Why isn't PNG offered as an output format here?
PNG compression is lossless and doesn't have a quality slider — re-encoding a PNG through canvas rarely shrinks it meaningfully. For a genuine size reduction, use the Image Format Converter to switch to JPEG or WebP instead.
What quality setting should I use?
70–85% is a good starting point for photos — it's usually visually indistinguishable from the original while cutting file size significantly. Go lower only if file size matters more than visual quality.
What happens to transparency?
JPEG doesn't support transparency, so transparent areas are filled with white before compressing. Use WebP if you need to preserve transparency while still compressing.